Because I loved it and I don’t love it for some time now.

For me it’s the opposite. I actually wasn’t too happy with GNOME 2 and all the problems it had with panel applets. It stored absolute pixels for their position on the panel (instead of relative positions, like Xfce does) and almost every time you plugged your laptop into a display with a different resolution, all your applets got randomly rearranged.

Then Ubuntu switched to Unity and I actually loved it, even though I didn’t understand (I was much younger back then) why I could no longer add eyes to my panel and why I couldn’t rearrange panels anymore. 😅 The locally integrated menu in later versions was great and I always loved the macOS-like look of the top panel for some reason.

GNOME Shell certainly was a huge learning curve and completely different to GNOME 2 and early versions were rough. But once Canonical made clear that it didn’t want to adopt Wayland and instead develop their own incompatible display server, I switched to GNOME Shell. Since I got used to it, I actually don’t mind it much and nowadays it has a very polished and professional feel to it.

I also think it is great that GNOME apps are convergent and work on mobile phones as well as on desktops. Makes the app availability for Linux phones better and reduces the amount of manpower required.